STM32 SPI获取磁性角度传感器AS5048A角度数据
时间：2022-09-22 11:00:01
STM32 SPI获取磁角传感器AS5048A角度数据
AS5048A采用14位精度磁角检测传感器SPI接口。事实上，稳定精度只有12位，即数据输出的最后两位在检测环境静止时发生变化而不恒定。AS5048A可用于旋转角度检测，如旋转编码器，特别是云台角度检测等Z轴旋转检测。
以下是官方模块：
因为AS5048A可以通过SPI也可以通过PWM线输出角度数据，第三方模块单独输出PWM还有单独输出的类型SPI这里只介绍一下SPI角度输出模式。
检测原理
磁角传感器的角度检测原理如下，需要半圆磁极的磁片配合，磁片旋转时，AS5048A检测磁线的变化，获取角度信息。
AS5048A它是一个360度检测传感器，用户可以设置0角位置。其优点是直接输出角度，不需要转换角速度到角度，测试验证长无零漂移。
SPI协议
AS5048A采用16位的SPI设置操作地址的命令发送格式如下：
写数据格式如下：
读取的数据格式如下：
AS5048A内部寄存器的功能如下：
读角操作模式
读取角度的操作方法可根据时序要求进行：
- 清除错误的寄存器指令
- 空操作指令
- 读角度指令
- 空操作指令
所以会发送4次SPI在最后一个空操作指令周期中收到的数据包含角度数据，因为指令采用全双工发收方式。
角度数据处理
角度数据有两种处理方法：
- 设置零点位置，然后直接使用读取的角度数据
- 零点位置不设置，STM32芯片上电时，先读取当前位置数据作为零点，然后进行算法处理。
以下例程采用第二种方式实现。
STM32例程
例程采用STM32F103ZET6芯片开发板和使用STM32CUBEIDE开发环境。
首先建立项目，设置时钟，外部8MHz时钟倍频到系统时钟。
采用USART1.配置异步串口输出数据USART1为115200波特率：
采用SPI1作为AS5048A配置通信接口：
SPI片选信号由GPIO逻辑控制，需要单独配置：
然后实现代码，通过串口输出角度数据，帧头为0x55 0xaa, 然后是2个字节16位的角度数据。360度对应0 ~ (16384-1)输出。
/* USER CODE BEGIN Header */ /** ****************************************************************************** * @file : main.c * @brief : Main program body ****************************************************************************** * @attention * * <h2>© Copyright (c) 2020 STMicroelectronics. * All rights reserved. * * This software component is licensed by ST under BSD 3-Clause license, * the "License"; You may not use this file except in compliance with the * License. You may obtain a copy of the License at: * opensource.org/licenses/BSD-3-Clause * ****************************************************************************** */
//Written by Pegasus Yu
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
#define __AS5048A2_CS_ENABLE() HAL_GPIO_WritePin(GPIOA, GPIO_PIN_4, GPIO_PIN_RESET)
#define __AS5048A2_CS_DISABLE() HAL_GPIO_WritePin(GPIOA, GPIO_PIN_4, GPIO_PIN_SET)
#define __Read_NOP 0xc000
#define __Read_Clear_Error_Flag 0x4001
#define __Read_Angle 0xffff
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
SPI_HandleTypeDef hspi1;
UART_HandleTypeDef huart1;
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_Init(void);
static void MX_USART1_UART_Init(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
uint16_t SPI_TX_DATA[10]={
0};
uint16_t SPI_RX_DATA[10]={
0};
const uint8_t op_num = 4;
uint16_t origin_value = 0;
uint8_t i;
uint8_t TXD[4]={
0};
uint16_t post_process_value=0;
/* USER CODE END 0 */
/** * @brief The application entry point. * @retval int */
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_SPI1_Init();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
TXD[0]=0x55; TXD[1]=0xaa;//frame head
SPI_TX_DATA[0] = __Read_Clear_Error_Flag;
SPI_TX_DATA[1] = __Read_NOP;
SPI_TX_DATA[2] = __Read_Angle;
SPI_TX_DATA[3] = __Read_NOP;
for (i = 0; i<op_num; i++)
{
__AS5048A2_CS_ENABLE();
HAL_SPI_TransmitReceive (&hspi1, &SPI_TX_DATA[i], &SPI_RX_DATA[i], 1, 2710);
__AS5048A2_CS_DISABLE();
HAL_Delay(1);
}
origin_value = SPI_RX_DATA[3]&0x3fff;
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
for (i = 0; i<op_num; i++)
{
__AS5048A2_CS_ENABLE();
HAL_SPI_TransmitReceive (&hspi1, &SPI_TX_DATA[i], &SPI_RX_DATA[i], 1, 2710);
__AS5048A2_CS_DISABLE();
HAL_Delay(1);
}
if ( (SPI_RX_DATA[3]&0x3fff)>=origin_value ) post_process_value= (SPI_RX_DATA[3]&0x3fff)-origin_value;
else post_process_value= 16384-origin_value+(SPI_RX_DATA[3]&0x3fff);
TXD[2] = (post_process_value&0xff00)>>8;
TXD[3]= post_process_value&0x00ff;
HAL_UART_Transmit(&huart1, TXD, 4, 0xffff);
HAL_Delay(1);
}
/* USER CODE END 3 */
}
/** * @brief System Clock Configuration * @retval None */
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {
0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {
0};
/** Initializes the CPU, AHB and APB busses clocks */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB busses clocks */
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
}
/** * @brief SPI1 Initialization Function * @param None * @retval None */
static void MX_SPI1_Init(void)
{
/* USER CODE BEGIN SPI1_Init 0 */
/* USER CODE END SPI1_Init 0 */
/* USER CODE BEGIN SPI1_Init 1 */
/* USER CODE END SPI1_Init 1 */
/* SPI1 parameter configuration*/
hspi1.Instance = SPI1;
hspi1.Init.Mode = SPI_MODE_MASTER;
hspi1.Init.Direction = SPI_DIRECTION_2LINES;
hspi1.Init.DataSize = SPI_DATASIZE_16BIT;
hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
hspi1.Init.CLKPhase = SPI_PHASE_2EDGE;
hspi1.Init.NSS = SPI_NSS_SOFT;
hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_32;
hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi1.Init.CRCPolynomial = 10;
if (HAL_SPI_Init(&hspi1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN SPI1_Init 2 */
/* USER CODE END SPI1_Init 2 */
}
/** * @brief USART1 Initialization Function * @param None * @retval None */
static void MX_USART1_UART_Init(void)
{
/* USER CODE BEGIN USART1_Init 0 */
/* USER CODE END USART1_Init 0 */
/* USER CODE BEGIN USART1_Init 1 */
/* USER CODE END USART1_Init 1 */
huart1.Instance = USART1;
huart1.Init.BaudRate = 115200;
huart1.Init.WordLength = UART_WORDLENGTH_8B;
huart1.Init.StopBits = UART_STOPBITS_1;
huart1.Init.Parity = UART_PARITY_NONE;
huart1.Init.Mode = UART_MODE_TX_RX;
huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart1.Init.OverSampling = UART_OVERSAMPLING_16;
if (HAL_UART_Init(&huart1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN USART1_Init 2 */
/* USER CODE END USART1_Init 2 */
}
/** * @brief GPIO Initialization Function * @param None * @retval None */
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {
0};
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOA_CLK_ENABLE();
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_4, GPIO_PIN_SET);
/*Configure GPIO pin : PA4 */
GPIO_InitStruct.Pin = GPIO_PIN_4;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}
/* USER CODE BEGIN 4 */
/* USER CODE END 4 */
/** * @brief This function is executed in case of error occurrence. * @retval None */
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/** * @brief Reports the name of the source file and the source line number * where the assert_param error has occurred. * @param file: pointer to the source file name * @param line: assert_param error line source number * @retval None */
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number, tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
此例程持续向USART1输出从AS5048A读取到的角度数据。
–End–
